[INFO] updating cached repository thomasfermi/JackCompiler
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/thomasfermi/JackCompiler
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/thomasfermi/JackCompiler" "work/ex/beta-1.37-6/sources/1.36.0/gh/thomasfermi/JackCompiler"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/1.36.0/gh/thomasfermi/JackCompiler'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/thomasfermi/JackCompiler" "work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/thomasfermi/JackCompiler"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/thomasfermi/JackCompiler'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] e8f6f882182fbb0d2485afd13155c2436f1a506f
[INFO] sha for GitHub repo thomasfermi/JackCompiler: e8f6f882182fbb0d2485afd13155c2436f1a506f
[INFO] validating manifest of thomasfermi/JackCompiler on toolchain 1.36.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of thomasfermi/JackCompiler on toolchain beta-2019-07-23
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing thomasfermi/JackCompiler
[INFO] finished frobbing thomasfermi/JackCompiler
[INFO] frobbed toml for thomasfermi/JackCompiler written to work/ex/beta-1.37-6/sources/1.36.0/gh/thomasfermi/JackCompiler/Cargo.toml
[INFO] started frobbing thomasfermi/JackCompiler
[INFO] finished frobbing thomasfermi/JackCompiler
[INFO] frobbed toml for thomasfermi/JackCompiler written to work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/thomasfermi/JackCompiler/Cargo.toml
[INFO] crate thomasfermi/JackCompiler already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing thomasfermi/JackCompiler against 1.36.0 for beta-1.37-6
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-2/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/thomasfermi/JackCompiler:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.36.0" "build" "--frozen"`
[INFO] [stdout] 1cbf6885dce8f8422ade7ae570ebaed1e22a0265ad6306f489292f7cfadf4df5
[INFO] running `"docker" "start" "-a" "1cbf6885dce8f8422ade7ae570ebaed1e22a0265ad6306f489292f7cfadf4df5"`
[INFO] [stderr]    Compiling peek-nth v0.2.0
[INFO] [stderr]    Compiling jack_compiler v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:68:13
[INFO] [stderr]    |
[INFO] [stderr] 68 |         let mut output_file_name = str::replace(
[INFO] [stderr]    |             ----^^^^^^^^^^^^^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.89s
[INFO] running `"docker" "inspect" "1cbf6885dce8f8422ade7ae570ebaed1e22a0265ad6306f489292f7cfadf4df5"`
[INFO] running `"docker" "rm" "-f" "1cbf6885dce8f8422ade7ae570ebaed1e22a0265ad6306f489292f7cfadf4df5"`
[INFO] [stdout] 1cbf6885dce8f8422ade7ae570ebaed1e22a0265ad6306f489292f7cfadf4df5
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-2/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/thomasfermi/JackCompiler:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.36.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] c1ba4a12abd11bea75888558c8fe67b9bf1d498150b4a31dea34c2f7cc3578d0
[INFO] running `"docker" "start" "-a" "c1ba4a12abd11bea75888558c8fe67b9bf1d498150b4a31dea34c2f7cc3578d0"`
[INFO] [stderr]    Compiling jack_compiler v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:68:13
[INFO] [stderr]    |
[INFO] [stderr] 68 |         let mut output_file_name = str::replace(
[INFO] [stderr]    |             ----^^^^^^^^^^^^^^^^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_mut)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.89s
[INFO] running `"docker" "inspect" "c1ba4a12abd11bea75888558c8fe67b9bf1d498150b4a31dea34c2f7cc3578d0"`
[INFO] running `"docker" "rm" "-f" "c1ba4a12abd11bea75888558c8fe67b9bf1d498150b4a31dea34c2f7cc3578d0"`
[INFO] [stdout] c1ba4a12abd11bea75888558c8fe67b9bf1d498150b4a31dea34c2f7cc3578d0
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-2/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/thomasfermi/JackCompiler:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.36.0" "test" "--frozen"`
[INFO] [stdout] f9d792844c2e17614fb54c42266a7b00356c328919f79af38c7bd652ceaf749e
[INFO] running `"docker" "start" "-a" "f9d792844c2e17614fb54c42266a7b00356c328919f79af38c7bd652ceaf749e"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.03s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/jack_compiler-1240d5f87233cd91
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "f9d792844c2e17614fb54c42266a7b00356c328919f79af38c7bd652ceaf749e"`
[INFO] running `"docker" "rm" "-f" "f9d792844c2e17614fb54c42266a7b00356c328919f79af38c7bd652ceaf749e"`
[INFO] [stdout] f9d792844c2e17614fb54c42266a7b00356c328919f79af38c7bd652ceaf749e